Modern technology has given rise to a wide variety of different electronic and/or communication devices that keep users in touch with one another, entertained, and informed. A wide variety of portable electronic devices are available for these purposes, such as: cellular telephones; personal digital assistants (“PDAs”); pagers; beepers; MP3 or other audio playback devices; radios; portable televisions, DVD players, or other video playing devices; watches; GPS systems; etc. Many people like to carry one or more of these types of devices with them when they exercise and/or participate in athletic events, for example, to keep them in contact with others (e.g., in case of inclement weather, injuries; or emergencies; to contact coaches or trainers; etc.), to keep them entertained, to provide information (time, direction, location, and the like).
Athletic performance monitoring systems also have benefited from recent advancements in electronic device and digital technology. Electronic performance monitoring devices allow for monitoring of many physical or physiological characteristics associated with exercise or other athletic performances, including, for example: speed and distance data, altitude data, GPS data, heart rate, pulse rate, blood pressure data, body temperature, etc. Specifically, these athletic performance monitoring systems have benefited from recent advancements in microprocessor design, allowing increasingly complex computations and processes to be executed by microprocessors of successively diminutive size. These modern microprocessors may be used for execution of activity recognition processes, such that a sport or activity that is being carried out by an athlete can be recognized, and information related to that sport or activity can be analyzed and/or stored.
Inherently, however, portable electronic device systems are often powered by limited power sources, such as rechargeable batteries. Accordingly, as the computations carried out by these devices have become increasingly complex, the power consumption of the integral processors carrying out the computations has significantly increased. Consequently, the usable time between battery recharges has decreased.
In some instances it may be desirable to place one or more processors associated with a portable electronic device into a low-power operational mode. As such, a processor executing a low-power operational mode may operate using a low clock rate/clock speed that is below an operating clock rate. However, a processor executing a low-power operational mode may not be able to maintain (continue executing) one or more timer processes (timers). As such, a portable electronic device using one or more timer processes may require that a processor continues to operate in a high-power operational mode, and hence, operate with an associated relatively high power consumption.
Aspects of this disclosure are directed towards novel systems and methods that address one or more of these deficiencies. Further aspects relate to minimizing other shortcomings in the art.